1. Field of the Invention
The present invention is useful in medical fields. In more detail, novel spiro compounds of this invention are useful as neuropeptide Y receptor antagonists and as agents for the treatment of various kinds of cardiovascular disorders, central nervous system disorders, metabolic diseases, and the like.
2. Description of the Prior Art
Neuropeptide Y (hereinafter referred to as NPY), a peptide consisting of 36 amino acids, was first isolated from porcine brain by Tatemoto et al. in 1982 [Nature, 296: 659 (1982)]. NPY is widely distributed in central nervous system and peripheral nervous system and plays various roles as one of the most abundant peptide in the nervous system. That is, NPY acts as an orexigenic substance in the central nervous system and markedly promotes fat accumulation via the mediation of the secretion of various hormones or the action of the nervous system. It is known that the continuous intracerebroventricular administration of NPY induces obesity and insulin resistance based on these actions (International Journal of Obesity, vol. 19: 517 (1995); Endocrinology, vol. 133: 1753 (1993)). It is also known that NPY has central effects, such as depression, anxiety, schizophrenia, pain, dementia and the like (Drugs, vol. 52, 371(1996). Further, in the periphery, NPY coexists with norepinephrine in sympathetic ending and is involved in the tonicity of the sympathetic nervous system. It is known that peripheral administration of NPY causes vasoconstriction and enhances the activities of other vasoconstrictive substances such as norepinephrine (British Journal of Pharmacology, vol. 95: 419 (1988)). It is also reported that NPY could participate in the development of cardiac hypertrophy as a result of the sympathic stimulation (Proceeding National Academic Science USA, Vol. 97, 1595(2000)).
On the other hand, it is reported that NPY is also involved in the secretory function of sexual hormones and growth hormone, sexual behavior and reproductive function, gastro-intestinal motility, bronchoconstriction, inflammation and alcohol preference (Life Science, vol. 55, 551(1994); The Journal of Allergy and Immunology, vol. 101, S345(1998); Nature, vol. 396, 366(1998)).
NPY has a variety of pharmacological effects which result from NPY binding to the NPY receptors. Other NPY related peptides, including peptide YY and pancreatic polypeptide also bind to the NPY receptors. It is known that these pharmacological effects are mediated by the action of, at least, five receptor subtypes with or without synergistic interactions. (Trends in Neuroscience, vol. 20, 294(1997)).
Y1: It is reported that the central effect mediated by NPY Y1 receptor includes the remarkable orexigenic effect (Endocrinology, vol. 137, 3177(1996); Endocrinology, vol. 141, 1011(2000)). Further, the Y1 receptor is reported to be involved in anxiety and pain (Nature, vol. 259, 528(1993); Brain Research, vol. 859, 361(2000)). In addition, the pressor effects mediated by the strong action of vasoconstriction in the periphery by NPY is also reported to be mediated by Y1 (FEBS Letters, vol. 362, 192(1995); Nature Medicine, vol. 4, 722(1998)).
Y2: It is known that the inhibitory effect on the release of various neurotransmitters in the sympathetic nerve endings is mediated by the NPY Y2 receptor (British Journal of Pharmacology, vol. 102, 41(1991); Synapse, vol. 2, 299(1988)) In periphery, NPY causes constriction of blood vessel or vas deferens directly or via the control of release of various neurotransmitters (The Journal of Pharmacology and Experimental Therapeutics, vol. 261, 863(1992); British Journal of Pharmacology, vol. 100, 190(1990)). In addition, inhibition of lipolysis in adipose tissues is known (Endocrinology, vol. 131, 1970(1992)). Further, the mu inhibition of ion secretion in the gastrointestinal tract is reported (British Journal of Pharmacology, vol. 101 247(1990)).
On the other hand, the inhibitory effect on the central nervous system functions such as memory and anxiety is also reported (Brain Research, vol. 503, 73(1989); Peptides, vol. 19, 359(1998)).
Y3: It is reported that NPY Y3 receptor is mainly located at brainstem and in the heart and is related to regulation of blood pressure and heart rate (The Journal of Pharmacology and Experimental Therapeutics, vol. 258, 633(1991); Peptides, vol. 11, 545(1990)). Further, it is known that the Y3 receptor is involved in the control of catecholamine secretion in adrenal gland ((The Journal of Pharmacology and Experimental Therapeutics, vol. 244, 468(1988); Life Science, vol. 50, PL7(1992)).
Y4: NPY Y4 receptor has high affinity for pancreatic polypeptide. The related pharmacological effects reported to be mediated by the Y4 receptor include the inhibition of pancreatic secretion and the gastro-intestinal motility (Gastroenterology, vol. 85, 1411(1983)). Further, it is reported that NPY enhances the secretion of the sexual hormone in the central nervous system (Endocrinology, vol. 140, 5171(1999)).
Y5: The effect mediated by NPY Y5 receptor includes feeding stimulation and accumulation of fat (Nature, vol. 382, 168(1996)); American Journal of Physiology, vol. 277, R1428(1999)). It is reported that the NPY Y5 receptor also mediates some CNS effects, such as seizure and epilepsy, or pain and the morphine withdrawal symptoms (Natural Medicine, vol. 3, 761(1997); Proceeding Academic Science USA, vol. 96, 13518(1999); The Journal of Pharmacology and Experimental Therapetics, vol. 284, 633(1998)). In the periphery, the Y5 receptor is reported to be involved in diuresis and hypoglicemic effect caused by NPY (British Journal of Pharmacology, vol. 120, 1335(1998); Endocrinology, vol. 139, 3018(1998)). NPY is also reported to enhance cardiac hypertrophy as a result of the sympathic accentuation (Proceeding National Academic Science USA, Vol. 97, 1595(2000)).
The effects of NPY occur by binding to the NPY receptors in the central or peripheral nervous system. Therefore, the action of NPY can be prevented by blocking the binding to NPY receptors. Substances antagonize NPY binding to NPY receptors may be useful for the prophylaxis or treatment of various diseases related to NPY, such as cardiovascular disorders (for example hypertension, nephropathy, heart disease, vasospasm), central nervous system disorders (for example bulimia, depression, anxiety, seizure, epilepsy, dementia, pain, alcoholism, drug withdrawal), metabolic diseases (for example obesity, diabetes, hormone abnormality), sexual and reproductive dysfunction, gastrointestinal motility disorder, respiratory disorder, inflammation or glaucoma and the like (Trends in Pharmacological Sciences, 15: 153(1994); Life Science,. 55, 551(1994); Drugs, vol. 52, 371(1996); The Journal of Allergy and Immunology, vol. 101, S345(1998); Nature, vol. 396, 366(1998); The Journal of Pharmacology and Experimental Therapeutics, vol. 284, 633(1998); Trends in Pharmacological Science, vol. 20, 104(1999); Proceeding National Academic Science USA, vol. 97, 1595(2000)).
Recently, according to the investigation of the present inventors, it has been found that some kind of NPY receptor antagonist is useful in the prophylaxis or treatment of hypercholesterolemia, hyperlipidemia and arteriosclerosis [International application publication WO99/27965].
The object of the present invention is to provide novel medicines which exhibit NPY antagonistic activities.
The present inventors have discovered that the compounds of the general formula (I): 
wherein Ar1 represents aryl or heteroaryl which may be substituted, the substituent being selected from the group consisting of halogen, nitro, lower alkyl, halo (lower) alkyl, hydroxy(lower)alkyl, cyclo(lower)alkyl, lower alkenyl, lower alkoxy, halo(lower) alkoxy, lower alkylthio, carboxyl, lower alkanoyl, lower alkoxycarbonyl, lower alkylene optionally substituted with oxo, and a group represented by formula of xe2x80x94Qxe2x80x94Ar2;
Ar2 represents aryl or heteroaryl which may be substituted, the substituent being selected from the group consisting of halogen, cyano, lower alkyl, halo(lower)alkyl, hydroxy(lower)alkyl, hydroxy, lower alkoxy, halo(lower)alkoxy, lower alkylamino, di-lower alkylamino, lower alkanoyl and aryl;
n represents 0 or 1;
Q represents a single bond or carbonyl;
T, U, V and W represent independently nitrogen atom or methine group which may have a substituent selected from the group consisting of halogen, lower alkyl, hydroxy and lower alkoxy, where at least two of them represent the said methine group;
X represents methine, hydroxy substituted methine (namely methine substituted by hydroxy) or nitrogen;
Y represents imino which may be substituted with lower alkyl, or oxygen;
exhibit NPY antagonistic activities and is useful as a therapeutic agent for treatment of various diseases associated with NPY, thereby completing the present invention.
Compounds of the present invention (I) are useful as agents for the treatment of various diseases related to NPY, that is, for example cardiovascular disorders (for example hypertension, nephropathy, heart disease, vasospasm, arteriosclerosis), central nervous system disorders (for example bulimia, depression, anxiety, seizure, epilepsy, dementia, pain, alcoholism, drug withdrawal), metabolic diseases (for example obesity, diabetes, hormone abnormality, hypercholesterolemia, hyperlipidemia), sexual and reproductive dysfunction, gastrointestinal disorder, respiratory disorder, inflammation, or glaucoma, and the like.
More particulary, compounds of this invention (I) is useful as agents for the treatment of bulimia, obesity, diabetes, and the like.
The present invention refers to compounds of the general formula (I), the salts, esters or N-oxide derivatives thereof, and the process for production and use.
In another embodiment, the present invention is related to the intermediate for producing the compound represented by the general formula (I). Specifically, it is related to the compound represented by the general formula (VI-1): 
wherein ROp represents hydrogen or optionally protected hydroxy; and t, u, v and w represent independently nitrogen atom or methine group which may have a substituent selected from the group consisting of halogen, lower alkyl, lower alkoxy and optionally protected hydroxy, where at least two of them represent the said methine group.